Pilots frequently wish to simulate a mission prior to actually flying the mission. By simulating the mission, a pilot can become familiar with the mission route and can either avoid or prepare in advance for any portions of the mission that may require special effort or attention. In order to simulate a mission route, a pilot initially defines the mission route, such as by means of a mission planning system (MPS) or the like. As known to those skilled in the art, a mission planning system receives input from a pilot that defines a plurality of points along the mission route. For example, the pilot typically defines the beginning and end point(s) of the mission as well as points along the route at which the aircraft will change direction. The pilot also defines points that identify the location of targets or other features of interest. In addition to merely entering the points, the pilot also indicates the significance of each point, such as by indicating that the point represents an airfield, a target, a point at which the aircraft will change direction or the like. Based upon the plurality of points defined by the pilot, the MPS constructs the mission route to include each of the plurality of points.
Once the pilot has defined the mission route, a terrain model designer determines the area for which terrain source data will be required. In this regard, terrain source data is typically obtained, not just along the mission route, but for some distance on either side of the mission route to permit the flight simulation to continue if the aircraft deviates from the mission route. The size of the area for which terrain source data is required is typically based, in part, upon the aircraft platform including the range of the sensors onboard the aircraft, the turning radius of the aircraft and any other aircraft parameter that affects the size of the area that will be viewed by the pilot or interrogated by the aircraft and its sensors. In this regard, some aircraft platforms are capable of gathering and analyzing more remote sensor data than other aircraft platforms and therefore generally require terrain source data to be collected for larger areas surrounding the mission route in order to properly simulate the planned mission.
Additionally, the terrain model designer must determine the resolution with which the terrain source data should be displayed. Typically, different portions of the terrain source data are displayed at different resolutions, each of which is typically defined by the terrain model designer. In this regard, the images in the vicinity of an airfield, a target or other feature of interest are generally defined with greater resolution than more general terrain that is somewhat removed from the mission route.
As described above, the terrain model designer must therefore determine the area for which terrain source data is required and the respective resolution of each different region within the area for which terrain source data is required in order to permit the proper images to subsequently be generated and presented to the pilot during flight simulation. As will be apparent, the determination of the area for which terrain source data is required and the respective resolution of each region within that area is not only a time-consuming task, but is also prone to errors.
Based upon the definition of the area, a terrain model designer then collects the terrain source data required to construct a terrain model for a simulated flight along the mission route. Among other things, the terrain source data includes digitized photographs of the area over which the mission route will be flown. In addition to imagery, the terrain source data includes elevational data defining the elevation of the terrain along the mission route and feature data defining a variety of features, including obstructions, targets and the like, along the mission route. The terrain model designer can collect at least some of the terrain source data from terrain source data that is stored in a local memory device. However, the terrain model designer oftentimes must collect additional terrain source data for areas along the mission route for which no terrain source data is locally stored. Additionally, even in instances in which the terrain source data is stored in a local memory device, the terrain model designer typically canvasses other sources of terrain source data to determine the availability of terrain source data that is of higher quality and/or more recent than the terrain source data that is stored in a local memory device. If terrain source data that is of higher quality and/or more recent is available, the terrain model designer will generally obtain the higher quality terrain source data for use during the flight simulation in lieu of the terrain source data that is already stored by a local memory device, but that is of a lower quality and/or is less recent.
Electronic collections of terrain source data are maintained by a variety of sources. For example, terrain source data may be available from the joint services imaging processing station (JSIPS), the Gateway Data Navigator (GDN), the United States Imagery and Geospatial Information Services (USIGS), the master environment library (MEL), weather service feeds, commercial databases and the like. For many of these sources, however, the terrain model designer must complete and submit appropriate documents requesting the terrain source data and, in some instances, must provide proof that the terrain model designer as well as the pilots and other personnel who will have access to the terrain source data have appropriate clearances to access and view the terrain source data. As will be apparent, the process of searching, collecting and assimilating the terrain source data can also be a time-consuming process.
Once the terrain source data has been collected, the terrain source data is generally processed in order to improve or refine the resulting image and to extract various features from the terrain source data. In this regard, software programs, such as the Imagine software package by ERDAS, Inc. of Atlanta, Ga., provide many standard image processing functions, such as image enhancement, image registration, image rectification, image mosaic functions and elevation extraction. Additionally, these conventional software programs provide two-dimensional feature extraction and three-dimensional feature extrusion as well as material classification. While these conventional software programs perform the various image processing and feature extraction functions, the terrain model designer must generally provide the proper data in the correct format and must manually initiate and interact with the software program to perform the desired image processing.
Following the image processing operations, the terrain model designer provides the terrain source data to a terrain modeling software. The terrain modeling software compiles the terrain source data to form a terrain model. As with image processing, a variety of software programs, such as the Terra Vista software package from Terrain Experts, Inc. of Tucson, Ariz., are commercially available for generating a terrain model based upon terrain source data. The terrain model can then be provided to a flight simulator and, more particularly, to the image generator of a flight simulator for generating the necessary images during a simulation of the mission by the pilot.
While the terrain model that is necessary to simulate the mission to be flown by the pilot can be constructed in the manner described above, the manual process of collecting and processing the terrain source data and constructing the terrain model is time-consuming and requires that the terrain model designer have substantial experience. For example, the terrain model designer must often locate and obtain terrain source data from a variety of different collections. In addition, the terrain model designer must oftentimes determine the area for which terrain source data is to be collected and the resolution of the terrain source data for different regions within the area in order to properly simulate the mission route with the desired degree of detail. As such, it would be desirable to develop an improved method and apparatus for generating the terrain model for display during a simulated flight along a predefined mission route that could reliably and accurately generate the terrain model in a more efficient manner while requiring less manual intervention.